Genetics And Plant Breeding - Study Mode

[#496] Who discovered 'X-rays' first
Correct Answer

(B) Rontgen

Explanation

Solution: W. C. Rontgen discovered X-rays first. W. C. Rontgen reported the discovery of X-rays in December 1895 after seven weeks of assiduous work during which he had studied the properties of this new type of radiation able to go through screens of notable thickness. He named them X-rays to underline the fact that their nature was unknown. X-radiation is a penetrating form of high-energy electromagnetic radiation. Most X-rays have a wavelength ranging from 10 picometers to 10 nanometers, corresponding to frequencies in the range 30 petahertz to 30 exahertz (3 × 10 16 Hz to 3 × 10 19 Hz) and energies in the range 145 eV to 124 keV.

[#497] When the composite sample is reduced to required size which is to be submitted to seed testing lab is
Correct Answer

(C) Submitted sample

Explanation

Solution: When the composite sample is reduced to required size it is to be submitted to seed testing lab is Submitted sample . The composite sample is formed by combining and mixing all the primary samples taken from the lot or container or bag. Submitted sample is a sample submitted to the testing station.

[#498] Group of plants with similar characteristics of any rank is termed
Correct Answer

(D) Taxon

Explanation

Solution: A Group of plants with similar characteristics of any rank is termed a taxon . A taxon is a group of one or more populations of an organism or organisms seen by taxonomists to form a unit. A taxonomic unit, whether named or not: i.e. a population, or group of populations of organisms that are usually inferred to be phylogenetically related and which have characters in common that differentiate.

[#499] The F 1 ratio of a backcross in monohybrid cross is
Correct Answer

(B) 1 : 1

Explanation

Solution: The F 1 ratio of a backcross in a monohybrid cross is 1 : 1 . The mating of a hybrid organism (offspring of genetically unlike parents) with one of its parents or with an organism genetically similar to the parent is known as a Back cross. The backcross is useful in genetics studies for isolating (separating) certain characteristics in a related group of animals or plants.

[#500] Sum total of deleterious genes present in species is known as
Correct Answer

(C) Genetic load

Explanation

Solution: The total of deleterious genes present in species is known as Genetic load. A genetic alteration that increases an individual's susceptibility or predisposition to a certain disease or disorder is known as a deleterious gene. Deleterious mutation load is the main contributing factor to genetic load overall. Load depends only on the deleterious mutation rate and not on the selection coefficient.